A new study led by researchers from Ben-Gurion University of the Negev, Harvard University, and the University of Leipzig has uncovered innovative biological evidence that diet can directly influence brain aging.

Published in Clinical Nutrition, the study examined brain MRI scans alongside detailed blood protein profiles (proteomics) over an 18-month dietary intervention.

The research identified specific proteins linked to accelerated brain aging, with blood levels that were altered following dietary intervention.

Understanding Brain Age Gap

Age-related neurodegenerative conditions, such as brain atrophy, do not always align with our chronological age. Factors such as diabetes, inflammation, hypertension, high cholesterol, and the accumulation of β-amyloid and tau proteins can speed up brain aging. The “brain age gap” is defined as the difference between a person’s MRI-predicted brain age and their actual chronological age.

A positive gap indicates an older brain age than expected signifying accelerated brain aging while a negative gap reflects a younger brain age, suggesting a slowdown in brain aging.

A higher brain age gap has been observed in various neurological conditions, including mild cognitive impairment and Alzheimer’s disease.

Green-MED Diet Targets Key Proteins Driving Brain Aging

There is evidence that Galectin-9, a protein from the Galectin family, is expressed in microglial cells in the brain and that, upon binding to the Tim-3 receptor, it may induce the production of pro-inflammatory cytokines, which may accelerate neurodegenerative processes in diseases like Alzheimer’s.  Elevated levels of Galectin-9 have been found in individuals with mild cognitive impairment and in the early stages of Alzheimer’s disease. 

Decorin is a structural protein of the extracellular matrix. High levels of Decorin in cerebrospinal fluid have been linked to early changes in Alzheimer’s disease.

Dafna Pachter, a Ph.D. student and the first author of the paper, adds: “In this study, we are taking a small step toward a new possibility  a simple, accessible, and affordable blood test that could, in the future, provide an indication of brain status by analyzing omics layers in the blood”.

In the current study, the green-MED diet, rich in polyphenols from sources such as Mankai, green tea, and walnuts, significantly reduced Galectin-9 levels and slowed the increase in Decorin. The anti-inflammatory activity of these components may explain the potential neuroprotective effect observed in the study.

Dr. Anat Yaskolka-Meir, postdoctoral research fellow at Harvard T.H. Chan School of Public Health and the co-first author of the paper, explains the importance of studying circulating proteomics in brain health: “Studying the circulating proteins in blood allows us to observe, in a real-life setting, how the brain’s aging processes are influenced by lifestyle and dietary changes.

“This approach gives us a dynamic window into brain health, helping to reveal biological changes long before symptoms may appear. By mapping these protein signatures, we gain powerful new insight into how interventions, such as diet, may help preserve cognitive function as we age.”

Source: Green Mediterranean Diet Slows Brain Aging - Neuroscience News